The present invention generally relates to indoor air treatment systems, and more specifically, but not exclusively, concerns a mechanical and natural process dehumidifier with a compact construction that incorporates a heat recovery ventilation system that utilizes a high efficiency particulate air (HEPA) filter and an ultra-violet sanitation system.
Indoor air quality has become an increasing concern for new and newly remodeled home owners. Newer model homes over the past couple of decades have become more energy efficient and practically airtight.
Life inside today""s airtight homes generates both moisture and pollutants. Maintaining an ideal humidity in the home can be needed for optimum health. In order to create a comfortable living space, the humidity level in a home should be approximately 40-55%. When humidity levels are less than 40% or more than 60%, pollutant levels rise dramatically. This will cause bacteria, viruses, fungi, mites, respirator infections, allergic rhinitis and asthma, chemical interactions, and ozone production. With today""s tighter homes, too much humidity during all seasons can be problematic. For example, excessive moisture can cause the sweating/water drops to develop on windows and doorjambs. This condition is a major health concern and can prematurely deteriorate the windows and doorjambs. Areas of excessive moisture are also breeding grounds for mold, mildew, fungi, dust mites and bacteria. For example, black spots may form on the walls of humid homes, which indicate mildew growth. Mold spores and dust easily become airborne and circulate freely throughout the house, possibly causing a range of illnesses and allergic reactions.
In addition to excessive moisture and biological contaminants, appliances that utilize combustion have the potential for allowing gases such as carbon monoxide and other pollutants, to escape into the air. Some common sources may include gas ranges, water heaters, unvented space heaters, leaky chimneys, and wood burning appliances. Today""s homes have such high levels of negative pressure (because of exhausting appliances and fans in the home), that even a perfectly good chimney or appliance can be back drafted. Even breathing can add to the problem when carbon dioxide reaches excessive levels. Most building materials used today are treated with many harmful toxins that produce off gases that slowly leak into the home for many years. In addition, household cleaning products can generate large amounts of pollutants, and there is also a concern about radon seeping from the ground which may cause some health problems.
In a poor attempt to alleviate these problems, ventilation fans have been installed into rooms of homes, such as bathrooms, in order to draw stale air containing moisture and/or pollutants out of the home. However, operating such a fan reduces the overall energy efficiency and creates a severe negative pressure within the home. For instance, with an average run time of 20 minutes for a bathroom fan, approximately 2000 cubic feet of air is drawn out of the house. Replacement air is air drawn from outside the house and is unconditioned and unfiltered. This replacement air comes from the paths of least resistance, such as leaky doors and windows, chimneys, water heater vents, gas appliance vents, and attached garage. The replacement air must then be heated or cooled in order to match the inside air temperature. Further, this replacement air can worsen the air quality inside the home. During operation of the ventilation fan, when the humidity outside is greater than the inside humidity, humidity levels inside the home may in fact be increased to an uncomfortable level.
Portable air filters have been used to remove particulates, such as pollen and mold, from the air. While some of these portable filters advertise that they use a xe2x80x9cHEPA filterxe2x80x9d, in reality these filters are not true HEPA filters because they are not large enough to be at least 99.97% efficient in removing particles of at least 0.3 microns in diameter. With these types of inefficient filters, pollutants such as smoke, dust and bacteria can remain in the air. Another problem faced with portable air filtration systems is that such systems can only clean the air in limited areas of a house.
Therefore, there has been a need for an energy efficient, home air handling system that can be easily installed and that can maintain the relative humidity of a home at a comfortable level while at the same time, reducing the amount of pollutants in the air.
One form of the present invention concerns a unique air treatment system. The system includes a housing that defines an interior cavity. The interior cavity has a supply-air flow path and a stale-air flow path. A HEPA filter is positioned in the interior cavity of the housing along the supply-air flow path in order to filter supply air. A heat recovery core is positioned downstream from the HEPA filter along the supply-air flow path. The heat recovery core is positioned in the interior cavity between the supply-air flow path and the stale-air flow path to exchange heat between the supply air and stale air. An evaporator is positioned downstream from the heat recovery core along the supply-air flow path to remove heat from the supply air. An ultraviolet light is positioned downstream from the evaporator along the supply-air flow path to irradiate the supply air with ultraviolet light. A condenser is positioned downstream from the ultraviolet light along the supply-air flow path to reintroduce the heat removed from the supply air by the evaporator.
Another form of the present invention concerns a unique air treatment system. The system includes a housing that defines an interior cavity. The interior cavity has a supply-air flow path and a stale-air flow path. The housing includes a stale air chase for supplying stale air to the stale-air flow path and a tempered air chase for exhausting supply air from the supply-air flow path. The stale air chase and the tempered chase parallelly extend the entire length of one side of the housing. The housing defines a fresh air intake and a recirculation air intake. A baffle is provided along the supply-air flow path in the housing, and the baffle is positionable to alternately close the fresh air intake and the recirculation air intake. A charcoal filter is positioned downstream from the fresh air intake and the recirculation air intake along the supply-air flow path in the interior cavity to filter the supply air. A high efficiency particulate air filter is positioned downstream from the charcoal filter along the supply-air flow path to filter the supply air. A heat recovery core is positioned downstream from the high efficiency particulate air filter along the supply-air flow path. The heat recovery core is positioned between the supply-air flow path and the stale air flow path to exchange heat between the supply air and the stale air. An evaporator is positioned downstream from the heat recovery core along the supply-air flow path to cool the supply air. A drain pan is positioned in the interior cavity to collect condensation from the evaporator. An ultraviolet light is positioned downstream from the evaporator along the supply-air flow path to irradiate the supply air with ultraviolet light. A condenser is positioned downstream from the ultraviolet light along the supply-air flow path to heat the supply air. A supply air fan is positioned downstream from the condenser along the supply-air flow path to exhaust the supply air into the tempered chase. A stale air fan is positioned downstream from the heat recovery core along the stale air flow path to move the stale air. A compressor is positioned in the interior cavity of the housing, and the compressor is operatively coupled to the evaporator and the condenser. An electrical panel positioned in the housing to supply electricity to the system.